Francis s



UNITED STATES PATENT OFFICE.

FRANCIS S. COBURN, OF IPSWICH, MASSACHUSETTS, ASSIGNOR TO RUGGLES, NOURSE, MASON & CO.

SCREW-WRENCH.

Specification of Letters Patent No. 12,935, dated May 22, 1855.

To all 'whom t may concern Be it known that I, FRANCIS S. COBURN, of Ipswich, in the county of Essex and State of Massachusetts, have invented an Improved ScreW-Wrench, which I do hereby declare is fully described and represented in the following specification and the accompanying drawings, letters, figures, and references thereof, such ligures being denominated l and 2 and being, respectively, a side view and a longitudinal section of the article.

In carrying out my invention I afiX to one i end of a handle\A, a head, C, perforated with a passage D, of the form as seen in the drawings, arranging one of the diagonals of such passage in the line or plane of the axis of the handle. A portion B, of the head or of that corner of it which is next to the handle should be movable with respect to the rest, and be affixed to` a bar E so applied to the handle as to slide axially therein, and so that that part B, (which may be termed the jaw) may be moved toward the opposite angle o-r recess, I) c d, of the passage D, as occasion may require.

To the handle A, and slide bar E, a screw, E, should be so adapted, that when revolved it may produce a movement of the bar E in a longitudinal direction. For this purpose,

away from the angle of the opposite sides of the passage D, the faces of the notch of the jaw and the opposite sides'of the recess always remain at right angles with each other whereby the wrench would be readily adapted to a square nut. or head of a screw.

Arranging and combining with the angular recessed head, C, of a handle, A, a movable notched jaw operated in manner with respect to the recess of the head and by means substantially as described, the same rendering the wrench adjustable to nuts or screw heads of different sizes, and capable at the same time of embracing them on their four sides.

In testimony whereof, I have hereunto set my signature this fourteenth day of April A. D. 1853.

FRANCIS s. ooBURN.

l/Vitnesses:

CALEB EDDY, F. P. HALE, J r. 

